How to retain form values on redirect/validation on the same page?

I have a registration from that includes the Check New Username behaviour and also Server Validations. I have the value of the form fields set to:

value="<?php echo(ValidatedField("dreamcarukregister_655","FORENAME")) ?>"

..for each field so that if validation fails the form does not wipe the entered values.

However if validation is passed but the Check New Username behaviour fails, which redirects to the same page but with a querystring appended so that I can display a custom error message, the form fields are wiped blank.

How do I retain the values entered in the form on this redirect?
http://www.dreamcargalaxy.com/dreamcar-register.php

Thank you.
NJ

Use the "Unique value in database" server validation from within the server validations instead of the separate check new username server behavior.

Have applied that and I'm just getting a white page on Submit now (attached).

Can you please explain Unique Column, Key Column and Key value? The Help button on this dialog no longer loads a help page.

Unique column is the field we're checking against, right? In this case the e-mail address field. Key column is? The unique row ID? And Key value? Urggh...now I'm lost.

Whatever way I'm doing it, and I've tried a few, it's crashing the page.
Hope you can help. Thank you.
NJ

Unique column is the field you are checking against.

Key Column and Key Value are only used on update pages to make sure that it doesn't count the actual row being updated when ensuring the value is unique.

I think the issue was that you have an older version of the server validation scripts that didn't work with MySQLi. I've updated that on your site and it appears to work now.

Error...."Please specify a value for the "Key value" field" if I try to leave that blank.

What file have you updated, sorry?

I had updated the registration page and the validation include file. You can put in "-1" for the unique key value.

The validation include file?

wavt_scripts_php.php

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